Puncture Resistant Insole

ABSTRACT

A puncture resistant insole includes: a rigid plate shaped to contour a human foot and adapted to be inserted into a foot wear; a non-woven fabric layer enclosing adhesively the rigid plate from an exterior thereof; an antiseptic-deodorant fabric layer enclosing adhesively the non-woven fabric layer from an exterior thereof; and a polymer layer enclosing the antiseptic-deodorant fabric layer from an exterior thereof.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an insole for a foot wear, and more particularly to a puncture resistant insole for footwear, such as a pair of shoes, which provides comfortable wearing and which can prevent the foot of wearer from being injured by sharp objects, like nails or pointed rocks owing to puncture of the shoe.

2. The Prior Arts

In order to provide flexibility and quietness, majority of footwear are fabricated from flexible substance, like rubber. To be more specific, the bottom surface of the footwear is generally formed with pattern so as to enhance the friction to prevent the wearer from slipping off, thereby causing unwanted injury to the wearer. For those people working in a hazardous environments, like lumberjacks in jungles, construction workers in construction sites and nail or knife-making factories where sharp and pointed objects available anywhere, those people are always exposed to dangers since they may step over and thus the shoes may be punctured any time, thereby causing unnecessary injuries. The situation is aggravated if the footwear or the shoes are fabricated from rubber.

U.S. Pat. No. 6,871,422 has proposed a protective insert for footwear so as to prevent occurrence of shoe puncture. The protective insert according to said patent includes a single stainless steel sheet upon which upper surface, a molded polymer layer is provided adhesively such that once inserted into the shoe, the steel sheet is located at the bottommost part of the shoe so that even if the shoe is punctured by a sharp object, no injury will be done on the foot of the wearer.

One drawback of the abovementioned protective insert resides in that the polymer layer may offset in position relative to the steel sheet or peel off the steel sheet after long time of use.

SUMMARY OF THE INVENTION

A primary objective of the present invention is to provide a puncture resistant insole, which provides comfortable wearing and which can prevent the foot of wearer from being injured by sharp objects, like nails or pointed rocks owing to puncture of a shoe once the insole is inserted into the shoe.

One aspect of the present invention resides in that several woven and non-woven fabric layers are provided adhesively so as to enclose a rigid plate. Finally, a polymer layer is provided to enclose the assembly of the rigid plate and the woven and non-woven fabric layers in such a manner to prevent separation relative to one another so as to provide sufficient flexibility and comfortable feeling when wearing the shoes in which a pair of puncture resistant insoles is inserted therein to cushion the wearer's feet.

A puncture resistant insole of the present invention accordingly includes a rigid plate shaped to contour a human foot and adapted to be inserted into a foot wear; a non-woven fabric layer enclosing adhesively the rigid plate from an exterior thereof; an antiseptic-deodorant fabric layer enclosing adhesively the non-woven fabric layer from an exterior thereof; and a polymer layer enclosing the antiseptic-deodorant fabric layer from an exterior thereof Preferably, the polymer layer is selected and fabricated from a material group consisting of polyurethane (PU), Thermoplastic elastomers (TPE), Ethylene vinyl acetate (EVA), Silicone, foam and rubber.

In this embodiment, the rigid plate is fabricated from stainless steel sheet.

In the above insole of the present invention, the rigid plate should have 8 mm thickness in order to provide sufficient rigidity and flexibility while walking.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which:

FIG. 1 shows a perspective view of a puncture resistant insole of the present invention;

FIG. 2 shows a cross-sectional view of the puncture resistant insole of the present invention;

FIGS. 3A-3D respectively illustrate the steps of fabricating the puncture resistant insole of the present invention; and

FIG. 4 is an enlarged view of an encircled portion L shown in FIG. 3D.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, wherein FIG. 1 shows a perspective view of a puncture resistant insole S of the present invention; and FIG. 2 shows a cross-sectional view of the puncture resistant insole S of the present invention. As illustrated, the puncture resistant insole S of the present invention is adapted to be inserted into a footwear, such as shoes, so as to cushion the foot of the wearer (not shown) and includes a rigid plate 1, a non-woven fabric layer 2, an antiseptic-deodorant fabric layer 3 and a polymer layer 4.

In this embodiment, the rigid plate 1 is shaped to contour a human foot and is adapted to be inserted into a foot wear. The non-woven fabric layer 2 is formed in such a manner to enclose adhesively the rigid plate 1 from an exterior thereof The antiseptic-deodorant fabric layer 3 is formed in such a manner to enclose adhesively the non-woven fabric layer 2 from an exterior thereof. Finally, the polymer layer 4 is formed in such a manner to enclose the antiseptic-deodorant fabric layer 3 from an exterior thereof.

Referring to FIGS. 3A-3D, wherein FIGS. 3A-3D respectively illustrate the steps of fabricating the puncture resistant insole S of the present invention. As illustrated, a flat long stainless steel sheet of 8 mm is punched to form a rigid plate 1 that is shaped to contour or a profile of a human foot, as best shown in FIG. 3A. The rigid plate 1 is washed with some appropriate chemical substance or solution so as to clean without dirt or waste. A special adhesive is sprayed onto the external surface of the rigid plate 1 so as to form a non-woven fabric layer 2 that entirely encloses the rigid plate 1 from an exterior thereof. Later, the assembly of the rigid plate 1 and the non-woven fabric layer 2 is put into a mold (not visible), where the assembly undergoes a high compression so that the non-woven fabric layer 2 is bond securely on the rigid plate 1 (see FIG. 3B). Then, the antiseptic-deodorant fabric layer 3 is formed on the non-woven fabric layer 2 and the assembly thereof is inserted into another mold (not visible), where a suitable pressure is applied thereon such that the antiseptic-deodorant fabric layer 3 is stacked securely and firmly on the non-woven fabric layer 2. Finally, the assembly of the rigid plate 1, the non-woven fabric layer 3 and the antiseptic-deodorant fabric layer 3 is again inserted into yet another mold (not visible), where polymer liquid is introduced into the yet another mold. After a predetermined time interval or when the polymer liquid solidifies entirely and hence forming the polymer layer 4, the puncture resistant insole S of the present invention is obtained by removing from the mold, as best shown in FIGS. 3D and 4. In this embodiment, the polymer layer 4 is selected and fabricated from a material group consisting of polyurethane (PU), Thermoplastic elastomers (TPE), Ethylene vinyl acetate (EVA), Silicone, foam and rubber.

When the puncture resistant insole S of the present invention is inserted into a shoe, the same provides a comfortable wearing feeling owing to the polymer layer 4 and since the rigid plate 1 provides a sufficient rigidity, the problem of the shoe being punctured by a sharp object can be avoided. In addition, since the non-woven fabric layer 2, the antiseptic-deodorant fabric layer 3 and the polymer layer 4 are securely and firmly fastened relative to one another, the problem of separation among them can also be avoided, not only providing durable and long wearing ability.

Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. 

What is claimed is:
 1. A puncture resistant insole comprising: a rigid plate shaped to contour a human foot and adapted to be inserted into a foot wear; a non-woven fabric layer enclosing adhesively said rigid plate from an exterior thereof; an antiseptic-deodorant fabric layer enclosing adhesively said non-woven fabric layer from an exterior thereof; and a polymer layer enclosing said antiseptic-deodorant fabric layer from an exterior thereof.
 2. The puncture resistant insole according to claim 1, wherein said rigid plate is fabricated from stainless steel.
 3. The puncture resistant insole according to claim 2, wherein said rigid plate has a thickness of 8 mm. 